Determination Of Heavy Metals and Radon Concentration in Soil and Water Samples from Wadi-B Jere Oil Exploration Sites in Maiduguri, Northeast Nigeria

Abstract

Radon gas and heavy metals are two significant risk factors that can cause lung cancer. Wadi B, a locality in Jere local government of Borno state, is an area where oil exploration is underway. There is a potential health risk of contamination of the drinking water and soil samples in the area. To investigate radon concentration and heavy metal contamination, several samples of water from wells and boreholes, as well as soil samples, were collected for analysis. The analysis was conducted using liquid scintillation (LSC) and atomic absorption spectrometry. The result of radioactivity analysis using LSC shows that water samples have varying levels of radon concentration ranging from 17.77 Bql-1 to 22.50Bql-1 which exceeded the maximum contaminant levels of 11.1Bq/L set by the USEPA 1999 and the world average value of 10Bq/L set by the World Health Organisation (WHO 2004). The mean annual effective cancer risk of radon intake varied across sampling points, ranging from 0.164, 0.246, 0.287 to 0.130, 0.218, and 0.227 for adults, children, and infants, respectively, with mean values of 0.146, 0.219, and 0.255. The mean values of excess lifetime cancer risk (ELCR) associated with radon inhalation and ingestion for adults, children, and infants were 0.0005110, 0.0007660, and 0.0008930, respectively. Moreover, elevated conductivity and total dissolved solids in water samples suggest potential contamination, exceeding the recommended limits set by the World Health Organization. On the other hand, Heavy metals analysis shows a mean value of ELCR 0.125009 for adults and 0.000063 for infants. Results showed that heavy metal concentrations in soil samples exceeded permissible limits for all metals except chromium and lead, with the order of concentration being Cr < Cd < Pb < Cu < Zn. These findings underscore the need for ongoing monitoring and remediation efforts to mitigate environmental and health risks in Wadi B